Studium odolnosti materiálŮ pro potrubní systémy proti koroznímu praskání

Piping systems of gas pipelines are made of grade 11 steel, and especially of material 11353. Corrosion attacks from the outside surface still remain a principal problem. In some cases, the problems also include corrosion cracking from the inside surface of the piping. A solution to the latter includes the identification of corrosive components of deposits by experimentally verifying the occurrence of corrosion cracking under given conditions, followed by draft measures to diminish their influence. The study is devoted to the first part of this procedure. It deals with conditions of the piping materials exposure and the identification of critical substances occurring in piping. A method of tensile experiments with slow deformation speed in a model environment was used to test specimens cut out of temperature-affected spiral weld zones. The experiments run in model environments revealed the propensity of the measured material to corrosion cracking in the environment of leachate from gas pipeline deposits. A temporary conclusion is drawn that it is some cations occurring in deposits that have the most significant part to play in the corrosion of grade 11 material under given conditions.